The invention relates to a system for adjusting a transmission ratio in a transmission built into a motor vehicle.
In the control of a stepped automatic transmission (AT), an automated manual shift transmission (ASG) or a continuously variable transmission (CVT), adaptive transmission controls are known, for example, from U.S. Pat. No. 5,157,609 and DE 41 36 613 C as well as the article from ATZ, Automobiltechnische Zeitschrift 94 (1992) 9, starting at page 428, and ATZ, Automobiltechnische Zeitschrift 95 (1993) 9, starting at page 420. In automatic transmissions, the transmission ratio changes are, in general, determined in dependence upon the vehicle longitudinal speed and the engine load (throttle flap angle). This takes place by means of a characteristic field. In adaptive transmission control systems, the characteristic field (with which the transmission ratio changes are determined) can be adapted to the behavior of the driver (driver type), to the traffic situation and/or to the traffic situation to which the vehicle is subjected. In classifying the behavior of the driver, it is generally evaluated whether the driver is more interested in a driving-power orientated driving or is more interested in a consumption-optimized driving. In the evaluation of the traffic situation or driving situation, one can, for example, distinguish whether the vehicle is in city traffic ahead of or in a curve, on a hill or in overrun operation. Depending upon the evaluation of the above-mentioned points, the particular suitable characteristic line is selected from a number of different characteristic lines. In addition, a shift of the basic shift characteristic field (as described in U.S. Pat. No. 5,857,161) can be provided.
The classification of the driver of a vehicle has a decisive influence on the selection of the transmission gear to be set in addition to the following: the so-called driving situations, such as an uphill travel, a driving on a slippery roadway (winter), a driving with a cold engine (warmup) or a driving in the curve (curve). As a rule, here, one distinguishes between the more fuel-consumption-orientated driver type and the more driving-power-orientated driver type in one, two or multiple steps or continuously. Various methods are known for determining the so-called driver type.
U.S. Pat. No. 5,351,776 discloses a hierarchically structured control of the elements of the drive train of a motor vehicle (for example, engine, clutch/torque converter, transmission). A software structure for determining the transmission ratio is shown in U.S. Pat. No. 6,216,077.
The object of the present invention is to so configure the determination the driver type that the system can be adapted in the simplest possible way to various requirements.
The system according to the invention for adjusting a transmission ratio in a transmission built into a motor vehicle includes at least two determining elements by means of which values are determined based on different determination modes which values represent the driving behavior of the driver of the motor vehicle. According to the invention, administration means are provided by means of which the determined values are called up from the determining elements. Then, at least one counter value is changed in the counting means in dependence upon the called-up values. Finally, the transmission ratio is set in dependence upon the outputted values.
As mentioned initially herein, the determination of a driver type for influencing the shift strategy of a stepped automatic transmission (AT), an automatic shift transmission (ASG) or a continuously variable transmission (CVT) is a method known for years. According to the present invention, the driver type detection is split up into variant parts and non-variant parts and thereafter modularized based thereupon. The system obtained in this manner is then imaged into an object-orientated model. In this way, a system of driver-type detection arises which offers special advantages in the maintenance, reusability and the applicability by the motor vehicle manufacturer. The method to use a driver type for influencing the shift strategy of a transmission to be adjusted automatically is, at the present time, differently represented by the motor vehicle manufacturers; whereas, some manufacturers have used these methods already for years and therefore already have a definite impression and accent as to the nature in accordance with which viewpoints a driver is to be determined; there are other manufacturers who have not up to now used a type of driver in the transmission control. The system according to the invention ensures a unitary determination sequence wherein the special wants of the vehicle manufacturers can be tied into the various parts. In order to provide a starting basis for the manufacturers, which up to now have not yet used a type of driver in the transmission control, a special accent of the various parts of the driver-type determination was developed in accordance with the invention which nonetheless makes a useable driver type available in an especially short and brief form. This accent functions as an example in the embodiment of the present invention.
In an advantageous configuration of the invention, determination means are provided with which a driver-type value is determined in dependence upon the instantaneous counter value and this driver type value represents the driving performance of the driver of the motor vehicle. The transmission ratio is adjusted at least in dependence upon the driver-type value.
In a further advantageous embodiment of the invention, the counting means are so configured that, in dependence upon the called-up values:
the counter value is incremented or decremented;
the counter value is set to a specific value; and/or,
an upper and/or lower limit for the counter value is set.
In an especially advantageous embodiment, it is provided that in the administration means it is stored which one of the determining elements can be called up and which one of the determining elements cannot be called up. Especially, the administration means can be so configured that at least one determining element is not called up, that is, it is never called up during driving operation or is deactivated.
The above-mentioned embodiment of the invention makes especially clear the advantage of the simple applicability. The different determining elements can, depending upon the wants of the vehicle manufacturer, contribute in any desired combination to the determination of the driver type. For this purpose, the (variant) administration means only have to be correspondingly programmed; whereas, the other components of the driver-type determination, especially the determination elements, remain unchanged.
In another advantageous embodiment of the invention, the administration means are so configured that the call-up of at least one of the determining elements takes place in dependence upon the determination of the value of another one of the determining elements. In this configuration of the invention, the (variant) administration means coordinate which of the determining elements can be active in which sequence, that is, which of the determining elements are permitted to actively supply their contribution to the driver-type determination in parallel to the other determining elements.
The determination means can be so configured that the instantaneous counter value is assigned pregivable time intervals and the driver-type value is determined from the assignment to one of the part intervals with the driver-type value representing the driving performance of the driver of the motor vehicle.
The determining elements can be so configured that:
during the start-drive operation of the vehicle, the position of the accelerator pedal, which is actuated by the driver, is evaluated to determine a first value which represents the driving performance of the driver of the motor vehicle; and/or,
the rate of change of the position of the accelerator pedal, which is actuated by the driver of the motor vehicle, is evaluated to determine a second value, which represents the driving performance of the driver of the motor vehicle; and/or,
exceeding of the position of the accelerator pedal, which is actuated by the driver of the motor vehicle beyond a pregivable threshold value is evaluated to determine a third value which represents the driving performance of the driver of the motor vehicle; and/or,
a fourth value, which represents the driving performance of the driver of the motor vehicle, is determined from the quotient of the position of the accelerator pedal, which is actuated by the driver of the motor vehicle, and the road speed of the motor vehicle.
The following advantages result with respect to the various criteria:
Simple applicability of the system of the invention: the priority of different aspects for the driver-type determination (different determining modes in the determination means) can be applied as desired in the administration means and without change of the determination means.
Expandability of the invention: the number of determining means is practically unlimited. The expansion of the driver-type recognition according to the invention is simple because the system of the invention makes available fixed defined interfaces. For a new determination means, only an identification code has to be given and made known in the administration means, that is, the identification code is stored.
Functionality of the system of the invention: the actual driver-type evaluation (in the determining elements, in the determination means and in the counting means) is not included in the prioritization (in the administration means). For this reason, a high flexibility is provided with respect to different requirements of various vehicle manufacturers.
The reusability of the system of the invention:
For different requirements of the total system, only the individual determining elements need be activated or deactivated or changed. The entire system and the structure for the driver-type recognition remain, however, unchanged.
For the same component requirements in a different context, individual determining elements can be simply exchanged because of the defined interfaces.
Transverse connections between determining elements for suitable prioritization (which could greatly inhibit reusability) are avoided by the prioritization by the administration means.